1. Field of the Invention
The present invention relates to an object detecting apparatus for determining a main object to be shot with emphasis, from within the shooting field.
2. Description of the Related Art
Conventionally, a camera has been widely known that has a microcomputer and automatically adjusts focus and exposure in order that shooting can be performed with an object constituting part of the shooting field as the reference. This camera generally has a structure as shown in FIG. 13. The camera 80 which has a photometer 81 detecting the brightness of the object and a pair of image detectors 82 calculates the distance to the object and the brightness of the object by a microcomputer 83 based on the signals from the photometer 81 and the image detectors 82, and adjusts a taking lens 84 based on the result of the calculation so that an image of the object is formed on imaging means 85.
A distance measurement frame indicating the distance measurement range is provided in the finder of this camera, and the user performs shooting while framing the picture so that the main object is captured in the frame. In order that the distance to the object captured in the distance measurement frame can be measured by the image detectors 82, distance measurement points normally disposed so as to be invisible are provided, and shooting can be performed with focus and exposure adjusted with respect to the object overlapping a distance measurement point.
However, when the distance measurement range of the camera is small, it sometimes occurs that an object behind the object to be shot is in focus. That is, when a picture is taken with the main object 88 not overlapping any of the distance measurement points 87 as shown in FIG. 14, the main object 88 is not in focus, so that a picture intended by the user cannot be taken.
To solve this problem, it has been proposed to perform focus lock by half depressing the release button as shown in FIG. 15. When the release button is half depressed with the main object 88 overlapping the distance measurement frame 89, since the main object 88 is present on a distance measurement point in the distance measurement frame 89, a condition where the main object 88 is in focus is fixed. Then, to obtain the composition intended by the user, the frame is moved with the half-depressed condition of the release button maintained, and then, the release button is fully depressed.
However, according to the focus lock, when a moving object such as a running child or a person participating in a sport is shot, it is difficult to determine when to half depress the release button. Moreover, the obtained picture is out of focus when the distance to the object which is once captured and on which focus is locked changes before the determination of the composition and shooting are actually performed.
On the other hand, an improvement has been made that distance measurement points are disposed in a wide range to increase the distance measurement range. This enables shooting to be performed with the main object as the reference even when the composition is such that the main object is not situated in the center. However, since it is difficult to select a main object in a wide distance measurement range, there are cases where an object not desired by the user is in focus.
Accordingly, to solve these problems, the present invention provides an object detecting apparatus capable of performing shooting with a main object desired by the user as the reference even when the object moves.